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1990-02-12
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═ODEM ╬OISE ╦ILLER
------------------
╫ITH SOME BASIC TOOLS INCLUDING A SOLDERING IRON, AND FOUR OR FIVE
COMPONENTS FROM ╥ADIO ╙HACK, YOU SHOULD BE ABLE TO CUT THE NOISE/GARBAGE
THAT APPEARS ON YOUR COMPUTER'S SCREEN.
╔ STARTED THIS PROJECT OUT OF FRUSTRATION AT USING A ╒╙ ╥OBOTICS 2400 BAUD
MODEM AND GETTING A FARE AMOUNT OF JUNK WHEN CONNECTING AT THAT SPEED.
╦NOWING THAT CAPACITORS MAKE GOOD NOISE FILTERS, ╔ THREW THIS TOGETHER.
╘HIS IS VERY EASY TO BUILD, HOWEVER CONDITIONS MAY BE DIFFERENT DUE TO MODEM
TYPE, AMOUNT OF LINE NOISE, OLD OR NEW SWITCHING EQUIPMENT (╘ELCO'S),
AND ON AND ON. ╙O IT MAY NOT WORK AS WELL FOR YOU IN EVERY CASE. ╔F IT DOES
WORK, OR IF YOU'VE MANAGED TO TWEAK IT TO YOUR COMPUTER/MODEM SETUP ╔'D LIKE
TO HEAR FROM YOU.
╔'D ALSO APPRECIATE ANY OF YOU ELECTRONIC WIZARDS OUT THERE WANTING TO OFFER
ANY IMPROVEMENTS. ╠ET'S MAKE THIS WORK FOR EVERYONE!
╨LEASE READ THIS ENTIRE TEXT AND SEE IF YOU UNDERSTAND IT BEFORE YOU BEGIN.
╧╦, WHAT YOU'LL NEED FROM ╥ADIO ╙HACK:
1 #279-374 ═ODULAR LINE CORD IF YOU DON'T ALREADY HAVE ONE. ┘OU WON'T NEED
ONE IF YOUR PHONE HAS A MODULAR PLUG IN ITS BASE. $4.95
1 #279-420 ═ODULAR SURFACE MOUNT JACK (4 OR 6 CONDUCTOR) $4.49
1 #271-1720 ╨OTENTIOMETER. ╘HIS IS A 5K AUDIO TAPER VARIABLE RESISTOR. $1.09
1 #272-1055 ├APACITOR. ┴NY NON-POLARIZED 1.0 TO 1.5 UF CAP SHOULD DO. ╨APER,
═YLAR, OR METAL FILM CAPS SHOULD BE USED, ALTHOUGH #272-996 MAY
WORK AS WELL. (272-996 IS A NON-POLARIZED ELECTROLYTIC CAP) $.79
1 100 OHM RESISTOR - QUARTER OR HALF WATT. $.19
1 #279-357 ┘-TYPE OR DUPLEX MODULAR CONNECTOR. ─ON'T BUY THIS UNTIL YOU'VE
READ THE SECTION ON CONNECTING THE ╬OISE ╦ILLER BELOW. (┴, ┬,OR
├) $4.95
╞IRST OFF, OPEN THE MODULAR BLOCK. ┘OU NORMALLY JUST PRY THEM OPEN WITH A
SCREWDRIVER. ╔NSIDE YOU'LL FIND UP TO 6 WIRES. ╓ERY CAREFULLY CUT OUT ALL
BUT THE GREEN AND RED WIRES. ╘HE ONES YOU'LL BE REMOVING SHOULD BE BLACK,
YELLOW, WHITE, AND BLUE. ╘HESE WIRES WON'T BE NEEDED AND MAY BE IN THE WAY.
╙O CUT THEM AS CLOSE TO WHERE THEY ENTER THE PLUG AS POSSIBLE. ╘HE OTHER
END OF THESE WIRES HAVE A SPADE LUG CONNECTOR THAT IS SCREWED INTO THE
PLASTIC. ╒NSCREW AND REMOVE THAT END OF THE WIRES AS WELL. ╬OW, YOU SHOULD
HAVE TWO WIRES LEFT. ╟REEN AND RED. ╙OLDER ONE END OF THE CAPACITOR TO THE
GREEN WIRE. ╙OLDER THE OTHER END OF THE CAPACITOR TO THE CENTER LUG OF THE
POTENTIOMETER (THERE ARE THREE LUGS ON THIS CRITTER). ╙OLDER ONE END OF THE
RESISTOR TO THE RED WIRE. ┘OU MAY WANT TO SHORTEN THE LEADS OF THE RESISTOR
FIRST. ╙OLDER THE OTHER END OF THE RESISTOR TO EITHER ONE OF THE REMAINING
OUTSIDE LUGS OF THE POTENTIOMETER. ─OESN'T MATTER WHICH. ╬OW TO WRAP IT UP,
MAKE A HOLE IN THE LID OF THE MOD BLOCK TO STICK THE SHAFT OF THE
POTENTIOMETER THROUGH. ─ON'T MAKE THIS HOLE DEAD CENTER AS THE OTHER PARTS
MAY NOT FIT INTO THE BODY OF THE MOD BLOCK IF YOU DO. ╙EE HOW THINGS WILL
FIT IN ORDER TO FIND WHERE THE HOLE WILL GO. ╫ELL, NOW THAT YOU'VE GOT IT
BUILT YOU'LL NEED TO TEST IT. ╞IRST TWIST THE SHAFT ON THE POTENTIOMETER
UNTIL IT STOPS. ┘OU WON'T KNOW WHICH WAY TO TURN IT UNTIL LATER. ╔T DOESN'T
MATTER WHICH WAY NOW. ┘OU ALSO NEED TO DETERMINE WHERE TO PLUG THE ╬OISE
╦ILLER ONTO THE TELEPHONE LINE. ╔T CAN BE DONE BY ONE OF SEVERAL WAYS:
┴. ╔F YOUR MODEM HAS TWO MODULAR PLUGS IN BACK, CONNECT THE ╬OISE ╦ILLER
INTO ONE OF THEM USING A LINE CORD. (A LINE CORD IS A STRAIGHT CORD THAT
CONNECTS A PHONE TO THE WALL OUTLET. ╒SUALLY SILVER IN COLOR)
┬. ╔F YOUR PHONE IS MODULAR, YOU CAN UNPLUG THE CORD FROM THE BACK OF IT
AFTER YOU'RE ON-LINE AND PLUG THE CORD INTO THE ╬OISE ╦ILLER.
├. ┘OU MAY HAVE TO BUY A ┘-TYPE MODULAR ADAPTOR. ╨LUG THE ADAPTOR INTO A
WALL OUTLET, PLUG THE MODEM INTO ONE SIDE AND THE ╬OISE ╦ILLER INTO THE
OTHER. ├ALL A ┬┬╙ THAT HAS KNOWN NOISE PROBLEMS. ┴FTER YOU'VE CONNECTED
AND GARBAGE BEGINS TO APPEAR, PLUG THE ╬OISE ╦ILLER INTO THE PHONE LINE AS
DESCRIBED ABOVE. ╔F YOU HAVE TURNED THE SHAFT ON THE POTENTIOMETER THE
WRONG WAY YOU'LL FIND OUT NOW. ┘OU MAY GET A LOT OF GARBAGE OR EVEN
DISCONNECTED. ╔F THIS HAPPENS, TURN THE SHAFT THE OTHER WAY UNTIL IT STOPS
AND TRY AGAIN. ╔F YOU DON'T NOTICE MUCH DIFFERENCE WHEN YOU PLUG THE ╬OISE
╦ILLER IN, THAT MAY BE A GOOD SIGN. ╘YPE IN A FEW COMMANDS AND LOOK FOR
GARBAGE CHARACTERS ON THE SCREEN. ╔F THERE STILL IS, TURN THE SHAFT SLOWLY
UNTIL MOST OF IT IS GONE. ╔F NOTHING SEEMS TO HAPPEN AT ALL, TURN THE SHAFT
SLOWLY FROM ONE SIDE TO THE OTHER. ┘OU SHOULD GET PLENTY OF GARBAGE OR
DISCONNECTED AT SOME POINT. ╔F YOU DON'T, REREAD THIS MESSAGE TO MAKE SURE
YOU'VE CONNECTED IT RIGHT.
***┼╬─ ╧╞ ╧╥╔╟╔╬┴╠ ╞╔╠┼***
┴──╔╘╔╧╬ ╘╧ ╧╥╔╟╔╬┴╠ ╞╔╠┼ - 2/29/88 - ═IKE ═C├AULEY -
╞IRST, A PERSONAL RECOMMENDATION. ñ╘╚╔╙ ╫╧╥╦╙!!!ñ ╔ HAVE BEEN PLAGUED WITH
NOISE AT 2400 FOR SOME TIME. ╔ WENT ROUND AND ROUND WITH ═A ┬ELL ON IT, AND
AFTER THEY SENT OUT SEVERAL "REPAIR PERSONS" WHO WERE, TO BE KIND, OF LIMITED
HELP IN THE MATTER, ╔ THREW IN THE TOWEL. ╔ SAW THIS FILE ON A BOARD UP EAST
A FEW DAYS AGO, AND THOUGHT ╔'D BITE. ╘HREW THE GISMO TOGETHER IN ABOUT 10
MINUTES, TOOK ANOTHER FIVE TO ADJUST THE POT FOR BEST RESULTS ON MY WORST
CONNECTION, AND GUESS WHAT? ╬O MORE WORST CONNECTION! ┴ FEW POINTERS:
1) ╘HE POT NEED NOT BE EITHER 5╦ OR AUDIO TAPER. ╔ USED A 10╦ 15 TURN TRIM POT.
╙UGGEST YOU USE WHAT IS HANDY.
2) ╔ USED 2═╞─'S OF CAPACITANCE (TWO 1═╞─'S IN PARALLEL) ╘WO ╥.╙. P/N 272-1055
WORK FINE. ╥EMEMBER THAT ABOUT 90 ╓OLTS WILL APPEAR ACROSS RED & GREEN AT
RING, SO THE CAPS SHOULD BE RATED AT 100╓─├+.
3) ╔ ENDED UP WITH A FINAL SERIES RESISTANCE VALUE (100 OHM + POT) OF 2.75╦.
╔ SPECULATE THAT ONE COULD PROBABLY USE 2═╞─ AND A FIXED 2.7╦ RESISTOR AND
DO THE JOB 90% OF THE TIME. ╘HE ADJUSTMENT OF THE POT IS NOT VERY CRITICAL.
├HANGES OF +/- 1╦ MADE LITTLE DIFFERENCE IN THE PERFORMANCE OF THE CIRCUIT.
╚OPE IT WORKS AS WELL FOR YOU AS IT DID FOR ME.
*****************************************************************************
┴ ╙╔═╨╠┼ ═╧─┼═ ╨╥╧╘┼├╘╧╥
------------------------
╔F YOU LIVE IN AN AREA OF THE COUNTRY THAT IS PRONE TO ELECTRICAL STORMS,
LIVE IN AN APARTMENT, HAVE ELECTRIC HEAT OR A DEHUMIDIFIER, THEN IT IS
CONCEIVABLE YOU NEED SPIKE PROTECTION FOR YOUR MODEM.
╙PIKE DEFLECTORS ARE COMMERCIALLY AVAILABLE BUT FOR WHAT THEY DO AND THE
PARTS INVOLVED, MOST ARE VERY OVERPRICED. ╞OR A RETAILER TO SELL YOU A
MODEM PROTECTOR IT MUST BE ╒/╠ LISTED IN THE ╒.╙.┴. OR ├╙┴ APPROVED IF YOU
LIVE IN ├ANADA. ╔T MAY ALSO, DEPENDING ON YOUR PHONE COMPANY, NEED TO BE
LISTED AS APPROVED EQUIPMENT BEFORE ATTACHING TO A PHONE LINE. ┴LL THIS
CERTIFICATION AND TESTING COSTS MONEY AND, AS ALWAYS, IT IS THE END USER
THAT PAYS.
╔F YOU ARE INTERESTED IN BUILDING YOUR OWN SPIKE DEFLECTOR, THEN READ ON.
╧THERWISE ╔ DO SUGGEST THAT YOU BUY A GOOD COMMERCIALLY AVAILABLE UNIT.
╧NE THING TO KEEP IN MIND WHEN BUYING A UNIT, IS TO READ THE WARRANTY, OR
GUARANTEE. ═OST WARRANTIES ONLY COVER THE SPIKE DEFLECTOR ITSELF AND DO
NOT COVER YOUR MODEM OR COMPUTER WHICH IS WHY YOU NEED SPIKE PROTECTION IN
THE FIRST PLACE.
╘HE SPIKE DEFLECTOR ╔ SUGGEST TO YOU IS DESCRIBED BELOW. ╔ HAVE HAD MINE
ON-LINE 24 HOURS PER DAY FOR NEARLY TWO YEARS. ╔N THAT TIME ╔ HAVE BEEN
HIT WITH SEVERAL LIGHTNING STORMS, SEEN THE DEVICE ACTIVATE TO DISCHARGE
THE LOAD, AND NOT SUFFERED ANY DAMAGE TO THE DEVICE, THE MODEM, OR THE
COMPUTER.
╬╧╘┼: ╔T IS VERY UNLIKELY FOR YOUR PHONE LINE TO TAKE A DIRECT LIGHTNING
STRIKE. ╔F YOU DO, THEN THERE IS LITTLE YOU CAN DO FOR PROTECTION. ┴
DIRECT HIT IS JUST AS LIKELY TO BURN YOUR HOUSE DOWN AS IT IS TO FRY YOUR
MODEM. ┴ SPIKE DEFLECTOR WILL ONLY OFFER A DEGREE OF SECURITY FOR MOST
INDIRECT HITS.
╘HE SPIKE DEFLECTOR.
-------------------
╨ARTS REQUIRED:
1. 2) ╬┼-2╚ ╬EON LAMPS (╥ADIO ╙HACK PART NO. 272-1102)
2. 2) 22K OHM RESISTORS (╥ADIO ╙HACK PART NO. 271-1339)
3. 1) ─UPLEX PHONE ╩ACK (╥ADIO ╙HACK PART NO. 279-357)
4. 1) ═ODULAR MALE ╩ACK (╥ADIO ╙HACK PART NO. 279-390)
... ┴LSO REQUIRED IS A PIECE OF INSULATED HOOK-UP WIRE (16-18 ┴╫╟).
─IRECTIONS:
----------
┴LL CONNECTIONS SHOULD BE SOLDERED AND ALL BARE WIRES, AND LEADS, SHOULD BE
INSULATED. ┘OU MIGHT USE SPAGHETTI INSULATION SCAVENGED FROM SOME WIRE, OR
ELECTRICAL TAPE.
╬╧╘┼: ╔F YOU MAKE ANY MISTAKES THERE IS VERY LITTLE DANGER OF CAUSING ANY
HARM TO YOUR PHONE LINE OR YOUR MODEM.
1) ╨╥┼╓┼╬╘ ╙╚╧╥╘ ├╔╥├╒╔╘╙: ├OVER EACH LEAD EMANATING FROM THE ╬EON WITH
ABOUT ONE HALF AN INCH OF INSULATING MATERIAL.
2) ├╥┼┴╘┼ ┴ ╬┼╧╬ ╥┼╙╔╙╘╧╥ ╨┴╔╥: ┴S CLOSE TO THE BODY OF A RESISTOR AS
POSSIBLE CONNECT ONE LEAD OF ONE ╬EON. ╙OLDER, REMOVE EXCESS LEAD AND TAPE.
┘OU SHOULD NOW HAVE TWO UNITS THAT ARE COMPOSED OF A ╬EON AND A RESISTOR.
3) ├╥┼┴╘┼ ╟╥╧╒╬─ ╨┴╘╚: ┴TTACH THE FREE ENDS OF BOTH RESISTORS TOGETHER
WITH A LENGTH OF INSULATED (16-18 ┴╫╟) WIRE. ╫IRE MUST BE LONG ENOUGH TO
REACH A GOOD GROUND CONNECTION. ═EASURE FROM THE PHONE OUTLET TO THE
NEAREST 110 VOLT OUTLET.
4) ├╥┼┴╘┼ ╨╚╧╬┼ ╨┴╘├╚-├╧╥─: ├UT MALE TO MALE MODULAR ╩ACK LEAD IN HALF.
╥EMOVE ABOUT ONE INCH OF THE OUTER INSULATION AND ABOUT ONE-HALF INCH OF
INSULATION FROM THE MIDDLE (RED AND GREEN) TWO CONDUCTORS. ╞OLD THE OUTER
WIRES (BLACK AND YELLOW) BACK ALONG THE LENGTH OF THE WIRE AND WRAP WITH
INSULATION.
5) ╞╔╬┴╠ ├╧╬╬┼├╘╔╧╬╙: ├ONNECT THE FREE END OF ONE OF THE ╬EONS TO ONE OF
THE EXSPOSED MIDDLE CONDUCTORS, AND THE OTHER ╬EON TO THE OTHER, INSULATED
FROM EACH OTHER.
╘EST ╒NIT:
---------
╔NSERT ═ALE CONNECTOR INTO THE DUPLEX PHONE JACK AND INSERT THE DUPLEX JACK
INTO YOUR TELCO'S PHONE JACK AND PLUG YOUR EXISTING PHONE OR MODEM INTO THE
OTHER JACK ON THE DUPLEX CONNECTOR. ─O NOT CONNECT THE LONG GROUNDING WIRE
JUST YET.
╘EST YOUR PHONE OR MODEM FOR PROPER OPERATION, BOTH DIALING OUT, AND
RECEIVING CALLS. ╔T IS PERFECTLY ╧.╦. IF ONE OR BOTH ╬EONS FLASH SLIGHTLY
WHILE DIALING OR RINGING. ╨AY PARTICULAR ATTENTION TO SEE THAT AFTER
A CALL (OUT-GOING OR INCOMMING) THAT YOU CAN PROPERLY HANG UP AND BE READY
FOR THE NEXT CALL WITHOUT HAVING TO ADJUST THE SPIKE DEFLECTOR.
╔F THE NEONS DO NOT FLICKER WHEN DIALING OUT, OR WHEN A CALL IS BEING
RECIEVED, YOU HAVE MADE A MISTAKE. ├HECK YOUR WIRING. ╔F THE LINE IS
CONSTANTLY BUSY TO AN INCOMMING CALL THERE IS ALSO A MISTAKE IN THE WIRING.
╔F TESTS ARE GOOD SO FAR, CONNECT THE LONG WIRE TO THE FACE-PLATE SCREW OF
THE NEAREST 110 VOLT OUTLET OR ANY GOOD KNOWN GROUNDING CONDUCTOR, ╫ATER
PIPE, ETC.
╥E-TEST THE SPIKE DEFLECTOR. ╔T SHOULD FLASH OCCASIONALLY, BUT PERMIT YOU
TO RECEIVE INCOMING CALLS, AND TO DIAL OUT. ╔F IT DOES NOT PERMIT NORMAL
PHONE OPERATIONS, THERE IS MOST LIKELY A MISTAKE IN YOUR CONNECTIONS.
╫HAT YOU HAVE ACCOMPLISHED, IF ALL HAS GONE WELL TO THIS POINT, IS TO
PROTECT YOUR MODEM FROM ANY OVER VOLTAGE CONDITION.
┘OUR PHONE COMPANY HAS A VESTED INTEREST IN NOT HAVING YOUR EQUIPMENT
HIT BY LIGHTNING AND HAS FUSES ON THE SYSTEM TO PROTECT YOU. ╘HE PROBLEM
IS THAT THE FUSES THEY EMPLOY ARE NOT ALWAYS FAST ENOUGH TO PROTECT YOUR
MODEM OR YOUR COMPUTER. ╘HEY ARE ONLY INTERESTED IN PROTECTING PHONES.
╘HE DEVICE YOU HAVE JUST BUILT WILL SHUNT ANY VOLTAGE OVER 70 TO GROUND AND
IF YOU ARE HIT BY 200 OR MORE, YOUR SAVING GRACE IS THAT THE SPIKE
DEFLECTOR WILL GREATLY LENGTHEN THE TIME THE FUSES ON YOUR LINE HAVE TO
RESPOND TO THE ANOMALY.
-------------------------
-------------------------